A quick reference guide for “at” utility in Sun Solaris. “at” utility in unix is similar to the “cron” daemon except for that “at” jobs are run only once while cron jobs are recurring. “at” is primarily used to schedule a job which can be command or a script to run once at a particular time although it can be made to reschedule the job. This could be immediatly or at a later time.

The at utility reads commands from standard input and groups them together as an at job, to be executed at a later time.

In the above -t switch defines the time that follows it as the time at which the one or more command that follows at the “at>” prompt to be run. Once, all the commands are entered press “CTRL+D” to make “at” aware of the end of commands.

Run a job now

sunsolaris# at nowat>reboot
at> <EOT>
commands will be executed using /sbin/sh
job 1210100190.a at Tue May 6 19:56:30 2008